A dual-energy radiation detection device includes two radiation detectors with different energy sensitivities, and detects radiation in a low-energy range (first energy range) and radiation in a high-energy range (second energy range) transmitted through a specimen. The radiation detectors have scintillator layers and pixels and generate a radiation image in the low-energy range and a radiation image in a high-energy range, respectively. With this radiation detection device, by simultaneously acquiring these radiation images and creating an image to which weighted subtraction processing and superimposition processing (for example, subtraction processing), etc., are applied based on these radiation images, detection of foreign substances, measurement of a component distribution, and measurement of weights, etc., can be realized with high accuracy in an in-line non-destructive inspection of a specimen that is conveyed by a belt conveyor, etc.
Radiation detection devices of this type are disclosed in Patent Literatures 1 and 2. In a baggage inspection device described in Patent Literature 1, a pixel width in a direction perpendicular to a pixel array direction in a high energy radiation detector is longer than a corresponding pixel width in a low energy radiation detector. Accordingly, beam levels of the low energy radiation detector and the high energy radiation detector can be made equivalent to each other. In the radiation detection device in X-ray CT described in Patent Literature 2, by using trapezoid radiation detectors, a pixel width in a direction perpendicular to a pixel array direction in the high energy radiation detector is made longer than a corresponding pixel width in a low energy radiation detector. Accordingly, radiation incidence amounts in the low energy radiation detector and the high energy radiation detector can be made equal to each other.